JPH085413Y2 - Cooling system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a cooling device in which a refrigerant is enclosed in an endless pipe, and is suitable for use in oil cooling of an automatic transmission.

<Prior Art> As shown in FIG. 3 which is a schematic cross-sectional view of a conventional automatic transmission, the left side of the drawing in the housing 11 transmits power by utilizing the energy of fluid motion to transmit the power to the clutch and the transmission. A torque converter 12 that functions as is provided. Further, on the right side of the drawing in the housing 11, there are provided a coupling device such as a clutch, a fixing device such as a belt brake, and a planetary gear device 13 including a planetary gear train and the like. Further, between the planetary gear unit 13 and the torque converter 12, the operation of the planetary gear unit 13 is controlled, and each element is connected / fixed / interrupted so that a required gear ratio with respect to the output of the torque converter 12 can be obtained. A shift control device 14 is provided which acts to obtain the shift.

In this way, the rotational movement of the engine (not shown) is transmitted to the input shaft 15 of the automatic transmission described above, further transmitted to the clutch of the planetary gear train 13 via the torque converter 12 and the gear shift control device 14, and the gear shift is performed in the planetary gear train. The output shaft 16 is reached.

Further, in the automatic transmission as described above, the oil for temporarily storing the lubricating or cooling oil sent to the above-described respective components such as the torque converter 12, the speed change control device 14, the planetary gear device 13, and the like. Bread 17 is provided. In this example, the oil pan 17 is integrally provided in the lower part of the housing 11 in which the speed change control device 14 and the planetary gear device 13 are located, and the oil stored in the oil pan 17 is supplied by an oil pump (not shown). After being pressure-fed to a required location in the automatic transmission, subjected to lubrication or cooling, it is returned to the oil pan 17 again. However, since it is essential that the oil collected in the oil pan 17 is sufficiently cooled and then sent to a necessary place, the cooling is conventionally performed by natural cooling by the outside air on the outer surface of the oil pan 17,
It was performed by an oil cooler (not shown) connected to the oil pan 17 by piping.

<Problems to be Solved by the Invention> In the conventional automatic transmission as shown in FIG. 3, the oil for lubrication and cooling that is sent to the necessary parts of each component is the oil provided in the lower part of the housing 11. It was temporarily stored in the pan 17 and cooled by natural heat dissipation from the outer surface of the oil pan 17. However, with only the natural heat dissipation,
Since the oil cannot be cooled sufficiently, a special oil cooler was installed separately from the automatic transmission,
If it is attempted to further improve the cooling efficiency of the oil, the size of the oil cooler is inevitably increased, and not only the cost is inevitably increased, but also the installation space is increased and the size of the entire configuration is increased, and the assembly difficulty is increased. There was a challenge to increase.

<Means for Solving the Problems> A cooling device according to the present invention is provided with a refrigerant passage formed in a wall of an automatic transmission housing and an automatic transmission that stays inside an oil pan attached to the automatic transmission housing. An annular cooling pipe, which is buried in cooling oil for use and has one end connected to one end of the refrigerant flow passage and the other end connected to the other end of the refrigerant flow passage, and at least stays inside the refrigerant pipe. And a refrigerant sealed inside the cooling pipe.

<Action> The refrigerant located in the vicinity of the cooling oil and staying in the refrigerant pipe absorbs heat from the cooling oil to be vaporized, and the vaporized refrigerant moves in the annular cooling pipe to be more than the cooling oil. It moves to the low temperature automatic transmission housing side, where it releases heat to the housing and liquefies again, then propagates in the cooling pipe and returns to the oil pan side again. Cooling oil is cooled by repeating such a cycle. <Example> Hereinafter, an example in which the cooling device according to the present invention is applied to an oil cooling device of an automatic transmission will be described in detail with reference to the drawings. The same members as those of the conventional technique will be denoted by the same reference numerals and detailed description thereof will be omitted.

The automatic transmission according to this embodiment is located above the oil pan 17, as shown in the schematic sectional view of FIG. 1 and the sectional view taken along the line AA in FIG. Housing 11
A plurality of (five in the present embodiment) refrigerant passages 21 through which the oil cooling refrigerant moves are formed in the wall thickness of the component of the gear shift control device 14 and the planetary gear device 13 in the casing 11. Is formed so as to surround. Furthermore, these refrigerant channels
Both ends of each of the 21 are opened so as to communicate with the inside of the oil pan 17 at the end of the housing 11 located on the oil pan 17 side (the lower part in the figure).

Both ends of the refrigerant flow passage 21 are connected by a refrigerant pipe 22 which is provided so as to be inserted into the oil stored in the oil pan 17, and the refrigerant flow passage 21 and the refrigerant pipe 22 described above are closed. It constitutes a substantially annular cooling pipe. A refrigerant 23 that can be efficiently vaporized by the oil collected in the oil pan 17 is enclosed in the cooling pipe, and the refrigerant 23 is in the refrigerant pipe 22 that is submerged in the oil of the oil pan 17 that is a heat source. In addition, it is mainly in a state of staying.

Therefore, due to the oil in the oil pan 17 having a high temperature due to the operation of the automatic transmission, the refrigerant in the refrigerant pipe 22 is vaporized while taking the heat of the oil and rises in the refrigerant pipe 22 to rise in the housing 11. It reaches the inside of the coolant channel 21. Further, the vaporized refrigerant is cooled by the outside air in contact with the outer surface of the housing 11 while moving upward in the refrigerant passage 21, and is condensed and liquefied again.
The liquefied refrigerant flows down through the refrigerant passage 21 again and returns to the inside of the refrigerant pipe 22 which is the heat source side. By repeating such a cycle, the oil in the oil pan 17 is cooled very efficiently.

Further, in this embodiment, in order to promote heat exchange between the refrigerant in the vaporized state in the refrigerant flow passage 21 and the outside air outside the housing 11, the outer surface of the housing 11 along each of the refrigerant flow passages 21 is A fin-shaped radiator 24 is provided so as to project.

By the way, in the present embodiment, the refrigerant flow path 21 and the refrigerant pipe 23 are configured to simply enclose the refrigerant 23 in the closed cooling pipe, but in addition, for example, inside the refrigerant flow path 21 and the refrigerant pipe 22. Alternatively, a member having a capillary structure for assisting the flow of the liquefied refrigerant may be attached. Further, the shape of the refrigerant pipe 22 is not limited to the rectangular shape as in this embodiment, and may be a spiral shape or the like in order to obtain a larger heat absorption area. Similarly, the refrigerant channel 21 formed in the housing 11
However, it may be formed by inclining or meandering in the left-right direction in the drawing so as to obtain a large heat dissipation area, and the present invention is not limited to this embodiment. Further, instead of the coolant channel 21, a coolant pipe may be provided along the inner surface or the outer surface of the housing 11.

<Effects of the Invention> According to the cooling device of the present invention, an annular cooling pipe is provided in contact with each of the cooling oil and the automatic transmission housing, and the refrigerant is retained in the cooling pipe mainly in the cooling oil side. By encapsulating, efficient cooling can be performed with an extremely simple structure, so that the device structure can be significantly downsized and the cost can be reduced.

[Brief description of drawings]

1 is a schematic sectional view showing an embodiment of a cooling device according to the present invention, FIG. 2 is a sectional view taken along the line AA in FIG. 1, and FIG.
FIG. 1 is a schematic sectional view of a conventional automatic transmission. In the drawing, 11 is a housing, 12 is a silk converter, 13 is a planetary gear device, 14 is a speed change control device, 17 is an oil pan, 21 is a refrigerant flow path, 22 is a refrigerant pipe, 23 is a refrigerant, and 24 is a radiator. .

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Yukihiro Hattori 5-3-8 Shiba, Minato-ku, Tokyo Inside Mitsubishi Motors Corporation (72) Inventor Takayasu Makino 5-3-8 Shiba, Minato-ku, Tokyo Within Mitsubishi Motors Corporation (56) References Japanese Patent Laid-Open No. 55-152393 (JP, A) Actual Development 61-58762 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A coolant flow path formed in a wall of an automatic transmission housing, and a coolant flow path which is buried in cooling oil for an automatic transmission that stays inside an oil pan attached to the automatic transmission housing, and one end of which is the coolant flow. An annular cooling pipe consisting of a refrigerant pipe connected to one end of the passage and the other end of which is connected to the other end of the refrigerant passage, and a refrigerant sealed inside the cooling pipe so as to stay at least inside the refrigerant pipe. A cooling device comprising: